If I keep the same 17 inch wheels and I don't lift my 2007 Rubicon any higher than it is, how much bigger on the tire size can I go and have it still be good on and off road? I have the tires it came with. BF Goodrich Mud Terrain 255/75/17. In other words 32's. Could I go to a 33 or 34 with out making any other changes or do I need to stay at a 32. How would increasing my tire size change my mpg as well?

 

Supposedly you can run a 33x10.5R17 w/o any rubbing issues. You might lose a bit on the MPG side, however, if you increase your tire size, you're changing your effective axle ratio and you should be cruising at a lower RPM thus increasing MPG in theory, but when you got alot more rubber, then it takes more energy to keep it moving. You might not even notice with such a small change expecially if the tire is the same width as stock

 

Please read:

https://www.jk-forum.com/forums/modified-jk-tech-2/modified-tech-faq-answers-questions-every-newbie-has-18617/

 

what is the width of the stock Rubicon Wheel?

 

Please read:

https://www.jk-forum.com/forums/show...74&postcount=3

Excerpt from FAQ thread:

Q: What are all the factory wheels that are available for the JK?
A:Factory wheel type and sizes listed below:

X Standard
Painted Steel - Size 16 x 7.0

X Optional
Painted Cast-Aluminum - Size 16 x 7.0 (2007)
Painted Cast-Aluminum - Size 17 x 7.5 (2008)

Sahara Standard
Painted Cast-Aluminum - Size 17 x 7.5

Sahara Optional
Painted Cast-Aluminum - Size 18 x 7.5

Rubicon Standard
Machined Cast-Aluminum - Size 17 x 7.5 Here's your answer.

Backspacing on all factory wheels is 6.25"

 

When I put my 305/70/17s Goodyear Wrangler MTRs on my factory Rubicon wheels it was after my 2" OME lift. I had read on here that 1.5" wheel spacers were needed in order prevent rubbing on the inside and they are but I was able to make it home from Discount tire without any rubbing. I had to put the spacers on myself afterwards because Discount tire said they can't touch anything with wheelspacers installed. The 305/70/17s are a 34 inch tire but I've been reading that once the tread wears they will eventually be 33s. In order to prevent rubbing the rear fender well I also needed to install 2" bumpstops. I'm sure these issues will be less felt with 33s.

Before the spacers were installed:


After the spacers were installed:

 

You have an awesome Jeep. I am looking to do the same thing. Did you install the additional OME spacer that came with the kit? I'm thinking the HD kit and the spacer might be too much. I think I'll go with the light duty coils and maybe install the spacer (or not) depending on how level it looks. I don't plan on getting after-market bumpers, so I think I'll be OK with light duty coils.

How do you like the MT/Rs? I had them on my TJ and liked them, but found that they wear fast and get loud after about 8-10k miles. I think I prefer my BFG Muds. I'm considering going with Toyo MT 285/75R17, which is also a 34" tire, but less wide than the GY MT/R. Dunno yet.

 

i was thinking the same thing. on an 09 ruby with no lift how big of tires can you go? could you get 35s in there if you went with flat/tube fenders? and maybe with some diff shocks?
just trying to not get it taller with a lift but with just bigger tires...thoughts?

 

how would putting on 33's instead of 32's benefit me when I am out four-wheeling?

 

I like your bumper mod. I done a few of those myself. LOL